From: Peter Zijlstra <peterz@infradead.org>
To: Tejun Heo <tj@kernel.org>
Cc: containers@lists.linux-foundation.org, cgroups@vger.kernel.org,
linux-kernel@vger.kernel.org, Li Zefan <lizefan@huawei.com>,
Michal Hocko <mhocko@suse.cz>,
Glauber Costa <glommer@parallels.com>,
Paul Turner <pjt@google.com>,
Johannes Weiner <hannes@cmpxchg.org>, Thomas Graf <tgraf@suug.ch>,
"Serge E. Hallyn" <serue@us.ibm.com>,
Paul Mackerras <paulus@samba.org>, Ingo Molnar <mingo@redhat.com>,
Arnaldo Carvalho de Melo <acme@ghostprotocols.net>,
Neil Horman <nhorman@tuxdriver.com>,
"Aneesh Kumar K.V" <aneesh.kumar@linux.vnet.ibm.com>
Subject: Re: [RFC] cgroup TODOs
Date: Fri, 14 Sep 2012 13:15:02 +0200 [thread overview]
Message-ID: <1347621302.7172.22.camel@twins> (raw)
In-Reply-To: <20120913205827.GO7677@google.com>
On Thu, 2012-09-13 at 13:58 -0700, Tejun Heo wrote:
> The cpu ones handle nesting correctly - parent's accounting includes
> children's, parent's configuration affects children's unless
> explicitly overridden, and children's limits nest inside parent's.
The implementation has some issues with fixed point math limitations on
deep hierarchies/large cpu count, but yes.
Doing soft-float/bignum just isn't going to be popular I guess ;-)
People also don't seem to understand that each extra cgroup carries a
cost and that nested cgroups are more expensive still, even if the
intermediate levels are mostly empty (libvirt is a good example of how
not to do things).
Anyway, I guess what I'm saying is that we need to work on the awareness
of cost associated with all this cgroup nonsense, people seem to think
its all good and free -- or not think at all, which, while depressing,
seem the more likely option.
next prev parent reply other threads:[~2012-09-14 11:18 UTC|newest]
Thread overview: 70+ messages / expand[flat|nested] mbox.gz Atom feed top
2012-09-13 20:58 [RFC] cgroup TODOs Tejun Heo
2012-09-14 9:04 ` Mike Galbraith
2012-09-14 17:17 ` Tejun Heo
2012-09-14 9:10 ` Daniel P. Berrange
2012-09-14 13:58 ` Vivek Goyal
2012-09-14 19:29 ` Tejun Heo
2012-09-14 21:51 ` Kay Sievers
[not found] ` <5052E7DF.7040000@parallels.com>
2012-09-14 9:12 ` Li Zefan
2012-09-14 11:22 ` Peter Zijlstra
2012-09-14 17:59 ` Tejun Heo
2012-09-14 18:23 ` Peter Zijlstra
2012-09-14 18:33 ` Tejun Heo
2012-09-14 17:43 ` Tejun Heo
2012-09-17 8:50 ` Glauber Costa
2012-09-17 17:21 ` Tejun Heo
2012-09-14 11:15 ` Peter Zijlstra [this message]
2012-09-14 12:54 ` Daniel P. Berrange
2012-09-14 17:53 ` Tejun Heo
2012-09-14 14:25 ` Vivek Goyal
2012-09-14 14:53 ` Peter Zijlstra
2012-09-14 15:14 ` Vivek Goyal
2012-09-14 21:57 ` Tejun Heo
2012-09-17 15:27 ` Vivek Goyal
2012-09-18 18:08 ` Vivek Goyal
2012-09-14 21:39 ` Tejun Heo
2012-09-17 15:05 ` Vivek Goyal
2012-09-17 16:40 ` Tejun Heo
2012-09-14 15:03 ` Michal Hocko
2012-09-19 14:02 ` Michal Hocko
2012-09-19 14:03 ` [PATCH 2.6.32] memcg: warn on deeper hierarchies with use_hierarchy==0 Michal Hocko
2012-09-19 19:38 ` David Rientjes
2012-09-20 13:24 ` Michal Hocko
2012-09-20 22:33 ` David Rientjes
2012-09-21 7:16 ` Michal Hocko
2012-09-19 14:03 ` [PATCH 3.0] " Michal Hocko
2012-09-19 14:05 ` [PATCH 3.2+] " Michal Hocko
2012-09-14 18:07 ` [RFC] cgroup TODOs Vivek Goyal
2012-09-14 18:53 ` Tejun Heo
2012-09-14 19:28 ` Vivek Goyal
2012-09-14 19:44 ` Tejun Heo
2012-09-14 19:49 ` Tejun Heo
2012-09-14 20:39 ` Tejun Heo
2012-09-17 8:40 ` Glauber Costa
2012-09-17 17:30 ` Tejun Heo
2012-09-17 14:37 ` Vivek Goyal
2012-09-14 18:36 ` Aristeu Rozanski
2012-09-14 18:54 ` Tejun Heo
2012-09-15 2:20 ` Serge E. Hallyn
2012-09-15 9:27 ` Controlling devices and device namespaces Eric W. Biederman
2012-09-15 22:05 ` Serge E. Hallyn
2012-09-16 0:24 ` Eric W. Biederman
2012-09-16 3:31 ` Serge E. Hallyn
2012-09-16 11:21 ` Alan Cox
2012-09-16 11:56 ` Eric W. Biederman
2012-09-16 12:17 ` Eric W. Biederman
2012-09-16 13:32 ` Serge Hallyn
2012-09-16 14:23 ` Eric W. Biederman
2012-09-16 16:13 ` Alan Cox
2012-09-16 17:49 ` Eric W. Biederman
2012-09-16 16:15 ` Serge Hallyn
2012-09-16 16:53 ` Eric W. Biederman
2012-09-16 8:19 ` [RFC] cgroup TODOs James Bottomley
2012-09-16 14:41 ` Eric W. Biederman
2012-09-17 13:21 ` Aristeu Rozanski
2012-09-14 22:03 ` Dhaval Giani
2012-09-14 22:06 ` Tejun Heo
2012-09-20 1:33 ` Andy Lutomirski
2012-09-20 18:26 ` Tejun Heo
2012-09-20 18:39 ` Andy Lutomirski
2012-09-21 21:40 ` Tejun Heo
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